| Records |
Author  |
Argue, C.K.; Clayton, H.M. |
| Title |
A preliminary study of transitions between the walk and trot in dressage horses |
Type |
Journal Article |
| Year |
1993 |
Publication |
Acta Anatomica |
Abbreviated Journal |
Acta Anat (Basel) |
| Volume |
146 |
Issue |
2-3 |
Pages |
179-182 |
| Keywords |
Animals; Forelimb/physiology; Gait/*physiology; Hindlimb/physiology; Horses/*physiology; Locomotion/physiology; *Physical Conditioning, Animal |
| Abstract |
The object of this study was to determine the limb support sequence during the transitions from walk to trot and from trot to walk in dressage horses under saddle and to test the null hypothesis that the limb support sequence during the transitions is not related to the level of training. Sixteen dressage horses training at novice to FEI Grand Prix level were videotaped performing an average of 9 transitions each from walk to trot and from trot to walk. The 30-Hz videotapes were viewed in slow motion, and based on the limb support sequence the transitions were categorized into two types. In type 1 transitions there were no intermediate steps between the walk and trot sequences. Type 2 transitions were characterized by intermediate steps, including a single support phase. The Kendall rank-order correlation coefficient showed that a higher level of training was positively associated with an increased percentage of type 1 transitions for both walk-to-trot transitions (p < or = 0.05) and trot-to-walk transitions (p < or = 0.01). No significant preference for initiating or completing the trot on the left or right diagonal was found using the binomial test for individual horses and the Wilcoxon signed-ranks test for the group. |
| Address |
Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada |
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Place of Publication |
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| Language |
English |
Summary Language |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0001-5180 |
ISBN |
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| Notes |
PMID:8470463 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
3752 |
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| Author |
Barrey, E.; Desliens, F.; Poirel, D.; Biau, S.; Lemaire, S.; Rivero, J.L.L.; Langlois, B. |
| Title |
Early evaluation of dressage ability in different breeds |
Type |
Journal Article |
| Year |
2002 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
| Volume |
|
Issue |
34 |
Pages |
319-324 |
| Keywords |
Animals; Biomechanics; Breeding; Discriminant Analysis; Female; Forelimb; Gait/genetics/*physiology; Hindlimb; Horses/anatomy & histology/*genetics/*physiology; Male; Photography/veterinary; *Physical Conditioning, Animal; Sports |
| Abstract |
Dressage is one of the Olympic equestrian sports practiced in several countries using different horse breeds. Specific characteristics of the walk, trot and canter are required for dressage. It has been assumed that some of these traits could be selected for genetically and contribute to dressage performance. The purpose of this study was to compare the walk, trot and conformation characteristics in young horses of different breeds used for dressage. A total of 142 horses age 3 years were classified into 3 groups of breeds (German, French and Spanish saddle horses) and tested using the same procedure. The skeletal conformation measurements were made by image analysis. Gait variables of the walk and trot were measured by the accelerometric gait analysis system Equimetrix. Discriminant analysis could explain the variability between the groups by taking into account the walk (P<0.0003), trot (P<0.0001) and conformation variables (P<0.0001). Many gait and conformation variables were significantly different between the breeds. In summary, the German horses had gait characteristics more adapted for dressage competition, and the results of this group could be used as a reference for early evaluation in dressage. Purebred Spanish horses could be considered as a reference for collected gaits used for farm work and old academic dressage. The gait and conformation tests could be applied in a breeding or crossing plan to detect more accurately young horses with good dressage ability. |
| Address |
INRA, Station de Genetique Quantitative et Appliquee, Groupe Cheval, Jouy-en-Josas, France |
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English |
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Conference |
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| Notes |
PMID:12405708 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
3726 |
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| Author |
Barrey, E.; Galloux, P. |
| Title |
Analysis of the equine jumping technique by accelerometry |
Type |
Journal Article |
| Year |
1997 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
| Volume |
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Issue |
23 |
Pages |
45-49 |
| Keywords |
*Acceleration; Analysis of Variance; Animals; Forelimb/physiology; Hindlimb/physiology; Horses/*physiology; Locomotion/*physiology; Movement/physiology; Time Factors |
| Abstract |
The purpose of this study was to demonstrate the relationships between jumping technique and dorsoventral acceleration measured at the sternum. Eight saddle horses of various jumping abilities competed on a selective experimental show jumping course including 14 obstacles. An accelerometric belt fastened onto the thorax continuously measured the dorsoventral acceleration during the course. At each jump, 11 locomotor parameters (acceleration peaks, durations and stride frequency) were obtained from the dorsoventral acceleration-time curves. The type of obstacle significantly influenced the hindlimb acceleration peak at take-off and the landing acceleration peak (P<0.01). The poor jumpers exhibited a higher mean forelimb acceleration peak at take-off, a higher forelimb/hindlimb ratio between peaks of acceleration (F/H), and a lower approach stride frequency than good jumpers. Knocking over an obstacle was significantly associated with a low hindlimb acceleration peak at take-off and a high F/H ratio (P<0.01). In order to observe the continuous changes in the frequency domain of the dorsoventral acceleration during the approach and take-off phase, a Morlet's wavelet analysis was computed for each horse jumping over a series of 3 vertical obstacles. Different patterns of time-frequency images obtained by wavelet analysis were found when the horse either knocked over a vertical obstacle or cleared it. In the latter case, the image pattern showed an instantaneous increase in stride frequency at the end of the approach phase, and a marked energy content in the middle frequency range at take-off. |
| Address |
INRA Station de Genetique Quantitative et Appliquee, Groupe cheval, Jouy-en-Josas, France |
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English |
Summary Language |
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Expedition |
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Conference |
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| Notes |
PMID:9354288 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
3796 |
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| Author |
Bobbert, M.F.; Santamaria, S. |
| Title |
Contribution of the forelimbs and hindlimbs of the horse to mechanical energy changes in jumping |
Type |
Journal Article |
| Year |
2005 |
Publication |
The Journal of Experimental Biology |
Abbreviated Journal |
J Exp Biol |
| Volume |
208 |
Issue |
2 |
Pages |
249-260 |
| Keywords |
Animals; Biomechanics; Forelimb/*physiology; Hindlimb/*physiology; Horses/*physiology; Locomotion/*physiology; Muscle, Skeletal/*physiology; Time Factors |
| Abstract |
The purpose of the present study was to gain more insight into the contribution of the forelimbs and hindlimbs of the horse to energy changes during the push-off for a jump. For this purpose, we collected kinematic data at 240 Hz from 23 5-year-old Warmbloods (average mass: 595 kg) performing free jumps over a 1.15 m high fence. From these data, we calculated the changes in mechanical energy and the changes in limb length and joint angles. The force carried by the forelimbs and the amount of energy stored was estimated from the distance between elbow and hoof, assuming that this part of the leg behaved as a linear spring. During the forelimb push, the total energy first decreased by 3.2 J kg(-1) and then increased again by 4.2 J kg(-1) to the end of the forelimb push. At the end of the forelimb push, the kinetic energy due to horizontal velocity of the centre of mass was 1.6 J kg(-1) less than at the start, while the effective energy (energy contributing to jump height) was 2.3 J kg(-1) greater. It was investigated to what extent these changes could involve passive spring-like behaviour of the forelimbs. The amount of energy stored and re-utilized in the distal tendons during the forelimb push was estimated to be on average 0.4 J kg(-1) in the trailing forelimb and 0.23 J kg(-1) in the leading forelimb. This means that a considerable amount of energy was first dissipated and subsequently regenerated by muscles, with triceps brachii probably being the most important contributor. During the hindlimb push, the muscles of the leg were primarily producing energy. The total increase in energy was 2.5 J kg(-1) and the peak power output amounted to 71 W kg(-1). |
| Address |
Institute for Fundamental and Clinical Human Movement Sciences, Vrije Universiteit, van der Boechorstraat 9, NL-1081 BT Amsterdam, The Netherlands. MFBobbert@fbw.vu.nl |
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Place of Publication |
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Editor |
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English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0022-0949 |
ISBN |
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Expedition |
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Conference |
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| Notes |
PMID:15634844 |
Approved |
no |
| Call Number |
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Serial |
1895 |
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| Author |
Burns, T.E.; Clayton, H.M. |
| Title |
Comparison of the temporal kinematics of the canter pirouette and collected canter |
Type |
Journal Article |
| Year |
1997 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
| Volume |
|
Issue |
23 |
Pages |
58-61 |
| Keywords |
Animals; Forelimb/physiology; Gait/*physiology; Hindlimb/physiology; Horses/*physiology; Locomotion/*physiology; Movement/physiology; Time Factors; Videotape Recording; Walking/physiology |
| Abstract |
The objectives were to compare the temporal characteristics of canter pirouette strides with collected canter strides in elite dressage horses, and to determine whether the stride kinematics of the canter pirouettes fulfilled the requirements specified in the Federation Equestre Internationale Rules for Dressage Events. Eleven horses were videotaped (60 fields/s) during the individual medal competition at the 1992 Olympic Games. Temporal variables were extracted from the videotapes using standard methods. Two strides were analysed on each of the left and right leads and these were pooled to give mean values for the collected canter and the pirouettes. The pirouettes were completed in 4-9 strides, (mean of 6.4). In the collected canter strides, mean duration of the suspension was 0.013 s. There was no suspension in any of the pirouette strides, instead the stance phases of the leading forelimb and trailing hindlimb overlapped by a mean of 0.163 s. In 9 horses the trailing forelimb contacted the ground before the diagonal leading hindlimb in the collected canter, whereas in the pirouettes the leading hindlimb always made contact before the trailing forelimb (mean dissociation 0.164 s), giving the strides a distinct 4 beat rhythm. Due to increases in advanced placement between the diagonal limb pair and between the 2 forelimbs, the stride duration was longer in the pirouette (0.879 s) than the collected canter (0.629 s). It is concluded that the canter pirouette strides did not maintain the rhythm and timing of the the collected canter strides in any of the 11 horses. |
| Address |
Department of Veterinary Anatomy, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada |
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English |
Summary Language |
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Conference |
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| Notes |
PMID:9354291 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
3737 |
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| Author |
Bystrom, A.; Roepstorff, L.; Johnston, C. |
| Title |
Effects of draw reins on limb kinematics |
Type |
Journal Article |
| Year |
2006 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
| Volume |
|
Issue |
36 |
Pages |
452-456 |
| Keywords |
Animals; Biomechanics; Exercise Test; Forelimb/physiology; Head/physiology; Hindlimb/physiology; Horses/*physiology; Humans; Movement/physiology; Neck/physiology; Physical Conditioning, Animal/*methods/*physiology; Weight-Bearing/physiology |
| Abstract |
REASONS FOR PERFORMING STUDY: No data exist on the GRF-kinematics relation due to changes caused by equestrian interventions. HYPOTHESIS: Through the judicious use of draw reins the rider can influence the kinematics of the horse to meet stated goals of dressage training. Relating the results to previously published kinetic data of the same experiment implies a possible relationship between kinetics and kinematics. METHODS: The kinematics of 8 sound Swedish Warmblood horses were measured whilst the horses were being ridden with and without draw reins. Three conditions were evaluated: 1) draw reins only (DR), 2) combination of draw reins and normal reins (NR+DR) and 3) normal reins only (NR). RESULTS: Head and neck angles were significantly decreased by the draw rein but 4-5 times more so for DR when with NR+DR. The forelimb position at hoof lift-off was significantly more caudal with DR. In the hind limb the hip joint extended more quickly and the hock joint flexed more with NR+DR than with NR. Compared to DR the hip joint angular pattern was not significantly different, but the pelvis was more horizontal. CONCLUSION: Riding with a draw rein can have significant influence on the kinematics of the horse. Some of the observed changes can be coupled to changes in kinetics. The hock joint angle seems to be a fairly reliable indicator of load on the hind limb and the angle of femur appears important for hind limb propulsion, when considered in conjunction with the orientation of the pelvis. POTENTIAL RELEVANCE: These findings are important for riders and trainers, as kinematic changes are what trainers observe. It is thereby important to ascertain which kinematic changes are consistently coupled to changes in kinetics in order for trainers to be able to judge correctly the success of intended goals. Further studies are warranted to validate and confirm suggested relationships between kinetics and kinematics. |
| Address |
Department of Equine Studies, Swedish University of Agricultural Sciences, S-750 07 Uppsala, Sweden |
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English |
Summary Language |
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Conference |
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| Notes |
PMID:17402465 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
3701 |
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| Author |
Cassiat, G.; Pourcelot, P.; Tavernier, L.; Geiger, D.; Denoix, J.M.; Degueurce, D. |
| Title |
Influence of individual competition level on back kinematics of horses jumping a vertical fence |
Type |
Journal Article |
| Year |
2004 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
| Volume |
36 |
Issue |
8 |
Pages |
748-753 |
| Keywords |
Animals; Back/*physiology; Biomechanics; Female; Forelimb/*physiology; Gait/*physiology; Hindlimb/*physiology; Horses/*physiology; Image Processing, Computer-Assisted; Imaging, Three-Dimensional/veterinary; Locomotion/physiology; Male; Video Recording |
| Abstract |
REASONS FOR PERFORMING STUDY: The costs and investments required for the purchase and training of showjumpers justify the need to find selection means for jumping horses. Use of objective kinematic criteria correlated to jumping ability could be helpful for this assessment. OBJECTIVES: To compare back kinematics between 2 groups of horses of different competition levels (Group 1, competing at high level; Group 2 competing at low level) while free jumping over a 1 m vertical fence. METHODS: Three-dimensional recordings were performed using 2 panning cameras. Kinematic parameters of the withers and tuber sacrale (vertical displacement, vertical and horizontal velocities), backline inclination and flexion-extension motion of the 3 main dorsal segments (thoracic, thoracolumbar and lumbosacral) were analysed. RESULTS: Group 2 horses had a lower displacement of their withers and tuber sacrale from the end of the last approach stride until the first departure stride (P<0.05). As a result, they increased the flexion of their thoracolumbar and lumbosacral junctions during the hindlimb swing phase before take-off (P<0.05). However, withers and tuber sacrale velocities were slightly modified. Group 1 horses pitched their backline less forward during the forelimb stance phase before take-off and straightened it more after landing (P<0.05), probably indicating a more efficient strutting action of their forelimbs. CONCLUSIONS AND POTENTIAL RELEVANCE: Because significant differences in back motion were found between good and poor jumpers when jumping a 1 m high fence, criteria based on certain back kinematics can be developed that may help in the selection of talented showjumpers. |
| Address |
UMR INRA-ENVA de Biomecanique et Pathologie Locomotrice du Cheval, Ecole Nationale Veterinaire d'Alfort, Avenue du General de Gaulle, 94704 Maisons Alfort, France |
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English |
Summary Language |
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Abbreviated Series Title |
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Edition |
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0425-1644 |
ISBN |
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| Notes |
PMID:15656509 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
4042 |
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| Author |
Clayton, H.M. |
| Title |
Classification of collected trot, passage and piaffe based on temporal variables |
Type |
Journal Article |
| Year |
1997 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
| Volume |
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Issue |
23 |
Pages |
54-57 |
| Keywords |
Analysis of Variance; Animals; Discriminant Analysis; Gait/*physiology; Hindlimb/physiology; Horses/*physiology; Locomotion/*physiology; Male; Running/physiology; Time Factors; Videotape Recording; Walking/physiology |
| Abstract |
The objective was to determine whether collected trot, passage and piaffe could be distinguished as separate gaits on the basis of temporal variables. Sagittal plane, 60 Hz videotapes of 10 finalists in the dressage competitions at the 1992 Olympic Games were analysed to measure the temporal variables in absolute terms and as percentages of stride duration. Classification was based on analysis of variance, a graphical method and discriminant analysis. Stride duration was sufficient to distinguish collected trot from passage and piaffe in all horses. The analysis of variance showed that the mean values of most variables differed significantly between passage and piaffe. When hindlimb stance percentage was plotted against diagonal advanced placement percentage, some overlap was found between all 3 movements indicating that individual horses could not be classified reliably in this manner. Using hindlimb stance percentage and diagonal advanced placement percentage as input in a discriminant analysis, 80% of the cases were classified correctly, but at least one horse was misclassified in each movement. When the absolute, rather than percentage, values of the 2 variables were used as input in the discriminant analysis, 90% of the cases were correctly classified and the only misclassifications were between passage and piaffe. However, the 2 horses in which piaffe was misclassified as passage were the gold and silver medallists. In general, higher placed horses tended toward longer diagonal advanced placements, especially in collected trot and passage, and shorter hindlimb stance percentages in passage and piaffe. |
| Address |
Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada |
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English |
Summary Language |
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Conference |
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| Notes |
PMID:9354290 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
3738 |
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| Author |
Clayton, H.M. |
| Title |
Comparison of the stride kinematics of the collected, working, medium and extended trot in horses |
Type |
Journal Article |
| Year |
1994 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
| Volume |
26 |
Issue |
3 |
Pages |
230-234 |
| Keywords |
Analysis of Variance; Animals; Biomechanics; Female; Forelimb/anatomy & histology/physiology; Gait/*physiology; Hindlimb/anatomy & histology/physiology; Horses/anatomy & histology/*physiology; Locomotion/physiology; Male; Motion Pictures |
| Abstract |
Highly-trained dressage horses were studied to test the hypothesis that stride length is altered independently of stride duration in the transitions between the collected, working, medium and extended trot. Six well-trained dressage horses were filmed at a frame rate of 150 frames/s performing the collected, working, medium and extended trots in a sand arena. Temporal, linear and angular data were extracted from the films, with 4 strides being analysed for each horse and gait type. There were no significant asymmetries between the left and rights limbs or diagonals when data from the whole group were pooled, but 3 horses showed asymmetries in one or more variables (P < 0.01). Analysis of variance and post-hoc tests indicated that the speed increased significantly (P < 0.01) from the collected (3.20 m/s) to the working (3.61 m/s) to the medium (4.47 m/s) to the extended (4.93 m/s) trot. The increases in speed were associated with a significant increase in stride length from 250 cm in the collected trot, to 273 cm in the working trot, 326 cm in the medium trot and 355 cm in the extended trot (P < 0.01). The lengthening of the stride was a result of increases between each gait type in the over-reach distance, whereas the diagonal distance was significantly longer in the extended than the collected trot only (P < 0.01). The stride duration tended to decrease as speed increased, and the difference became significant between the collected and extended trots (P < 0.01). |
| Address |
Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada |
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English |
Summary Language |
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Series Title |
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Abbreviated Series Title |
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Edition |
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0425-1644 |
ISBN |
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Conference |
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| Notes |
PMID:8542844 |
Approved |
no |
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Equine Behaviour @ team @ |
Serial |
3746 |
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| Author |
Dutto, D.J.; Hoyt, D.F.; Clayton, H.M.; Cogger, E.A.; Wickler, S.J. |
| Title |
Moments and power generated by the horse (Equus caballus) hind limb during jumping |
Type |
Journal Article |
| Year |
2004 |
Publication |
The Journal of Experimental Biology |
Abbreviated Journal |
J Exp Biol |
| Volume |
207 |
Issue |
Pt 4 |
Pages |
667-674 |
| Keywords |
Animals; Biomechanics; Hindlimb/*physiology; Horses/*physiology; Locomotion/*physiology |
| Abstract |
The ability to jump over an obstacle depends upon the generation of work across the joints of the propelling limb(s). The total work generated by one hind limb of a horse and the contribution to the total work by four joints of the hind limb were determined for a jump. It was hypothesized that the hip and ankle joints would have extensor moments performing positive work, while the knee would have a flexor moment and perform negative work during the jump. Ground reaction forces and sagittal plane kinematics were simultaneously recorded during each jumping trial. Joint moment, power and work were determined for the metatarsophalangeal (MP), tarsal (ankle), tibiofemoral (knee) and coxofemoral (hip) joints. The hip, knee and ankle all flexed and then extended and the MP extended and then flexed during ground contact. Consistent with our hypothesis, large extensor moments were observed at the hip and ankle joints and large flexor moments at the knee and MP joints throughout ground contact of the hind limb. Peak moments tended to occur earlier in stance in the proximal joints but peak power generation of the hind limb joints occurred at similar times except for the MP joint, with the hip and ankle peaking first followed by the MP joint. During the first portion of ground contact (approximately 40%), the net result of the joint powers was the absorption of power. During the remainder of the contact period, the hind limb generated power. This pattern of power absorption followed by power generation paralleled the power profiles of the hip, ankle and MP joints. The total work performed by one hind limb was 0.71 J kg(-1). Surprisingly, the knee produced 85% of the work (0.60 J kg(-1)) done by the hind limb, and the positive work performed by the knee occurred during the first 40% of the take-off. There is little net work generated by the other three joints over the entire take-off. Velocity of the tuber coxae (a landmark on the pelvis of the animal) was negative (downward) during the first 40% of stance, which perhaps reflects the negative work performed to decrease the potential energy during the first 40% of contact. During the final 60% of contact, the hip, ankle and MP joints generate positive work, which is reflected in the increase of the animal's potential energy. |
| Address |
Department of Kinesiology and Health Promotion, California State Polytechnic University, Pomona, CA 91768, USA. ddutto@csupomona.edu |
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English |
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0022-0949 |
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| Notes |
PMID:14718509 |
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no |
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Equine Behaviour @ team @ |
Serial |
3654 |
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